People's Language

S 14:4 And we have not sent any messenger except with the tongue of his people to clarify for them. And Allah misguides whom he wills and guides whom he wills. And he is the mighty, the wise.

No messenger was sent but with (sic) the tongue of his people. But what is a people's tongue or language? What might be, for example, that of the Jews? Do they have but one language or do they speak the language of the country that they were born in? Continuing with the Jews as an example, most of those born in the UK will speak English as a first language, those born in Germany will speak German, etc. Does 'tongue' refer to a people's original language? In my case, there would be at least two: Old English and a Celtic dialect.

Further reading:

Allah, his messengers, and their language